Primary prevention of venous thromboembolism in ambulatory cancer patients: recent advances and practical implications.

Venous thromboembolism (VTE) is a common complication in ambulatory cancer patients receiving anticancer therapies. Many patient-, cancer- and treatment-related factors along with specific biomarkers can be associated with an increased risk of VTE in patients with cancer. Risk assessment models such as the Khorana score serve as valuable tools to aid in the identification of patients with cancer who are at high risk of VTE. Two randomized controlled trials have evaluated the efficacy of primary thromboprophylaxis with low-dose direct oral anticoagulants, apixaban and rivaroxaban, to reduce the risk of VTE in ambulatory patients with cancer who are at intermediate to high risk of VTE identified by the Khorana score. This narrative review summarizes the literature on the risk factors and risk assessment process for VTE and the use of primary thromboprophylaxis in ambulatory cancer patients. We also outline important practical considerations for initiating primary thromboprophylaxis in this population.